Typewriting machine



"May 12, 1925.

' 1,537,767 P. M. GREENE .v -TYPEWRITIN MACHINE Filed July 29. 1924Patented May 12, 1925.

UNITED" STATES PATENT OFFICE.

PATRICK GREENE, OF HARTFORD, CONNECTICUT, ASSIGNOR TO ROYAL TYPE- WRITERCOMPANY, INC., OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

TYPEWRITING MACHINE.

Application filed July 29, 1924. Serial No. 728,863.

To all whom, it may concern.

Be it known that I, PATRICK M. GREENE, a citizen of the United States,and resident of Hartford, in the county of Hartford and State ofConnecticut, have invented certain new and useful Improvements inTypewriting Machines, of which the following is a specification.

The usual typewriting key comprises a cup carried by the upturned end ofthe key lever wherein are retained a washer, a disc or card carrying thecharacter, and a protecting glass. It frequently happens that althoughthis protecting glass is engaged by a ring member which has projectionsturned under the cup member and conse quently is supposed to hold theparts firmly in proper relation, nevertheless the character disc willbecome displaced.

An object of this invention is to provide simple and eflicient means forpreventing the displacement of the character disc, which means will notadd to the cost of manufacture or assembly or increase the number ofparts employed in the cap.

Other objects will be apparent from the following detailed descriptionand the appended claims.

In the drawings:

Figure 1 is a side elevation of the key lever with the assembled cap insection.

Figure 2 is a top plan view of the key lever, cup and washer.

Figure 3 is a top plan view of the washer.

Figure d is a side elevation of the same.

Figure 5 is a top plan View and Figure 6 a side elevation of a modifiedform of washer.

Figure 7 is a top plan view and Figure 8 a side elevation of a furthermodification.

Figure 9 is a top plan view and Figure 10 a side elevation of a stillfurther modiiication.

Figure 11 is a top plan view of character card shown as embedded in the.depressed portions of the washer.

The key lever A 'of ordinary form has an upturned end provided with areduced portion B which passes through a similarly shaped opening in acup member G and also through a similarly shaped opening I) in a washerD which fits within the cup. The end of the key lever portion B isriveted so that the lever, cup C and washer D are held rigidly together.Upon the washer D within the cup C is placed a character disc E,preferably of cardboard and having the desired character printedthereon. Over this is placed at protecting disc F of glass or othertransparent material. A ring G fits outside the cup and has an upperinwardly turned edge 9 which bears on the glass, while the lower edge ofthe ring G has ears 9 that are bent over the bottom of the cup C whenthe parts are assembled and draw the edge 9 down on the glass withconsiderable pressure, the intention being to hold the parts firmly inposition.

Notwithstanding this fact it frequently happens that the character discbecomes turned and when this happens it is ditlicult, if not impossible,to bring it back to proper position without disassembling the cap. Inaccordance with this invention there is pro vided a special form ofwasher which will engage the cardboard character disc and prevent itsdisplacement. Various forms may be devised, and four differentmodifications are illustrated, in all of which the washer D is soconstructed that portions thereof lie in dilferent planes. The pressureof assembly of the parts will therefore cause the raised portions of thewasher to be pressed into the cardboard character disc and the disc tobe pressed into the lower portions of the washer in such a manner thatany relative turning movement is positively prevented when the parts areassembled.

In the form shown in Figures 1 to 4, the washer D has two relievedportions d each of about one quarter of the circumference and separatedby equal spaces 07. Between these relieved portions the washer is spacedslightly from the wall of the cup G. The washeris not circular, butwould be substantially circular and fit loosely within the cup if theserelieved portions d were cut away. It will be seen that if thepasteboard character disc 1E ispressed down upon the washer D, theraised or relieved portions (1 will be imbedded in the cardboard, whilethe cardboard will be pressed down into the spaces d. Since the washeris held against rotation. it is evident that the character disc willalso be positively held against displacement.

It is obvious that washers of the desired form can be produced readilyby stamping and that there is no more difficulty in a'sseinbling theparts than in the old form. Nevertheless the character disc will be heldagainst any displacement without any special attention being given thematter of assembly. No additional parts are necessitated and thepressure of the character disc into the desired relation to the washerdoes not produce any noticeable distortion. Various forms of washer maybe devised which have the same general characteristics.

In the modifications shown in Figures 5 and 6, the washer D the portions(1 of the edge of the Washer are the same as those shown in the first.form, but the intervening portions 6 are pressed down instead of beingremoved as shown in Figure 3. When the parts are assembled the highportions (1 will be em bedded in the character disc.

In the modification shown in Figures 7 and 8, the washer D has threerelieved portions j which are .of less extent than the portions (1 ofthe preceding forms, but are separated by narrow cut away portions f.The action of the parts when assembled is the same as in the precedingcases. I

In the modification shown in Figures 9 and 10, the raised or relievededge of the washer D is divided into a plurality of portions, preferablyfour, which are, angularly arranged. The efl'eet, as clearly shown inthe drawings is to give a kind of spiral arrangement or fractions of amultiple screw thread. These portions H all have their upper ends lyingin a plane and their lower ends lying in a plane parallel thereto, butof course this is not essential and the particular form of these angularportions H may be widely varied.

It is obvious that further modifications may be readily devised withoutdeparting in any way from the spirit of the invention, and the inventionis to be regarded as limclaims.

I claim as my invention:

1. A key cap comprising a cup, a washer fitting therein, a characterdisc, and'means for pressing the character disc into engagement with theWasher, the latter being provided with engaging portions lying indifferent planes, whereby the disc and washer are positively held infixed relation when assembled.

2. A key cap comprising a cup, a washer fitting therein, a characterdisc, and means for pressing the character disc into engageited only bythe scope of the appended ment with the washer, the latter beingprowhich positively engage the disc when the parts are assembled andhold it againfi rela-.

tive rotation.

5. A key cap comprlsing a cup, a washer fitting therein, a characterdisc, and discontinuous surface portions on the washerinto interlockingengagement with which the disc is pressed when the parts are assembledto hold the disc against rotation.

In testimony whereof, I have hereunto subscribed my name.

PATRICK M. GREENE.

'on the washer lying in different planes-

